First version of new merge algorithm (not enabled yet)

Source/platform/graphics/paint/DisplayItem.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "platform/graphics/paint/DisplayItem.h"
 
 namespace blink {
 
 #ifndef NDEBUG
@@ skipping 88 matching lines @@
         return "End" + clipTypeAsDebugString(endClipTypeToClipType(type));
 
     PAINT_PHASE_BASED_DEBUG_STRINGS(FloatClip);
     if (isEndFloatClipType(type))
         return "End" + typeAsDebugString(endFloatClipTypeToFloatClipType(type));
 
     PAINT_PHASE_BASED_DEBUG_STRINGS(Scroll);
     if (isEndScrollType(type))
         return "End" + typeAsDebugString(endScrollTypeToScrollType(type));
 
+    PAINT_PHASE_BASED_DEBUG_STRINGS(SubtreeCached);
+    PAINT_PHASE_BASED_DEBUG_STRINGS(BeginSubtree);
+    PAINT_PHASE_BASED_DEBUG_STRINGS(EndSubtree);
+
     switch (type) {
     case BeginFilter: return "BeginFilter";
     case EndFilter: return "EndFilter";
     case BeginCompositing: return "BeginCompositing";
     case EndCompositing: return "EndCompositing";
     case BeginTransform: return "BeginTransform";
     case EndTransform: return "EndTransform";
     case BeginClipPath: return "BeginClipPath";
     case EndClipPath: return "EndClipPath";
     default:
@@ skipping 19 matching lines @@
         stringBuilder.append(", ");
     }
     stringBuilder.append("type: \"");
     stringBuilder.append(typeAsDebugString(type()));
     stringBuilder.append('"');
 }
 
 #endif
 
 } // namespace blink